In this Program Project we will study the effects of protein malnutrition on the developing brain. Anatomical, physiological, biochemical, and behavioral studies will be carried out in rats whose mothers were protein malnourished 5 weeks prior to mating and maintained on a low protein diet throughout pregnancy and lactation. The Neurochemistry group will seek to determine the effects of protein malnutrition on interrelations between insulin, glucagon, growth hormone, and corticosterone secretion and tryptophan metabolism during pre- and postnatal development. Additional neurochemical studies will determine to what extent protein malnutrition interferes with the interaction between biogenic amines and hormones, specifically growth hormone, and releasing and inhibitory factors such as somatostatin. Other investigations will determine how changes in brain enzymes such as tryptophan hydroxylase and tyrosine hydroxylase can be related to the increases in brain amines which have resulted from protein malnutrition. The physiology group will investigate how elevation of biogenic amines affects normal function of aminergic subsystems, i.e., locus coeruleus and raphe nuclei and their projections. These will serve as model systems for detailed electrophysiological analyses of the effects of malnutrition. Investigations of olfactory bulb electrophysiology will be carried out as a second major model system in which to study the effects of proten malnutrition. Additionally, we plan to follow-up previous findings on sleep and its perturbations produced by malnutrition and to complete a power spectral EEG atlas of the developing brain. A study of the effects of malnutrition on behavior will examine learning and memory, motor behavior and self-stimulation activity.